Detachable ski



Jan. 28 1930. A. n., s'rALB, JR 1,7455126 4nmmcfmm sin` me@ may 9, .192e

Patented Jan. 28, i930 UNITED :STATES PATENT OFFICE.

DETAGHABLE SKI Application :tiled Hay 9, 1928. Serial No. 276,289.

This invention relates to aircraft in general, and, in particular, to a new and improved landing means therefor.

In practice ,it has been found desirable at 6; times to land an aeroplane upon the surface of snow or ice. Hitherto it has been customary to replace the usual floats with which seaplanes may be provided` or the wheels of land planes .with skis for the purpose of 10 permitting the use of the aeroplane during the winter months or in a very cold climate.' The removal of the usual running gear makes it impossible to land the aeroplane on any other surface than snow or ice without danger of serious damage to the running gear and frame.

The general object of this invention is'to provide a means for landing an aeroplane on v the surface of snow or ice or upon-any smooth surface.

A- more specific object of -this invention is toprovide a means for permitting a seaplane to land on the surface of snow or ice without interfering with the use of its pontoons for landing on water. i s Another object of this invention is to provide a resilient shock absorbing means for attaching a ski to the bottom of the pontoon of a seaplane.

Another object of this invention is to provide means for detachably mounting a ski on the landing gear of an aeroplane.

Gther objects and advantages of this invention will become apparent from the following specification, claims and appended drawings, in which Y Fig. 1 is a vertical elevation showing a ski attached to the bottom of an aeroplane pontoon.

Fig. 2 isy a vertical longitudinal section showing the construction of. the ski and the means forattaching it to the pontoon.

Fig. Sis a transverse section taken on the line 3--3 of Fig. 1 and viewed in the direction of the arrows in that figure.

Fig. 4 is a vertical transverse view, partly `in section, showing the constructionof the resilient members.

50 Referring to the drawings and Figs. 1 and 2 in particular, the numeral 1 represents a ski adapted to be attached to the bottom of a seaplane pontoon. The ski 1 may be constructed of any suitable material and in any desired manner but is shown in the drawings as being constructed of layers of wood in order to secure both lightness and strength. Each of the skis 1 has the general shape shown in Fig. 2 and is detachably'connected` to the pontoon 2 in a manner now to be described. v

Extending longitudinally along the bottom of each pontoon 2 and in spaced relationship with each other and to the' front of the step are two angle bars 3 which are bolted or otherwise detachably fastened firmly to the pontoon. The ski 1 lies between the two angle bars 3, as best shown in Figs. 1 and 3, and is pivotally attached to the angle bars by i'neans of a bolt 4 which passes thru holes in the angle bars and also thru a hole in a nose piece 5. The nose piece 5 is attached to the forward end of th'e ski 1 by means of plates 6 and bolts or screws 7 e The whole purpose of this construction is to permit the ski 1 to rock about the bolt 4 as a pivot im order to allow the ski to give in response 4to the shocks incidental to the landing of the seaplane on a relatively hard surface such as snow or i'ce. It is also desirable that the'- ski be so attached as to be readily removed when not required or when repairs may be necessary. v In order to reduce the injurious effect produced by the shock of landin'gon snow or ice 'the rear ends of the skis are attached to the bottoms'of the pontoons by means of resilient members which act as shock absorbers. Any number of such resilient members may be provided and they may be placed in any desired position along the ski, but for conveniencein description and to reduce the number of drawings, the ski shown and now to be described has been provided with only two resilient members connecting the rear end of the ski with the bottom of a pontoon. The resilient members are alike in all respects and a description of one will suliice for all.

, Mounted upon the rear end of the ski 1 are pedestals 8 which are bolted firmly to the ski. Mounted upon and pivoted to the pedestals 8 are tubular members 9, which are pivoted to the pedestals by means of screw studs 10. The screw studs 10 pass thru holes in the pedestal 8, and holes in a reinforcing member 11 and screw firmly into holes in the tubular members 9. Each tubular member 9 is flared out or enlarged at its upper end as shown more clearly in Figs. 1 and 4.

Fitting smoothly within each tubular member 9 is a bushing or tube 12 which extends downwardly to a point just below the pivots 10 and is likewise flared out or enlarged so as to fit the flare in the tubular member 9. A tube 13 fits smoothly within the tube 12 and is adapted to slide freely in an axial direction within the tube 12. A head piece 14 is provided for each tube 13 and is rigidly attached to tube 13 by means of any suitable nature as by a bushing 15 which passes thru holes in the head piece 14 and the upper end of the tube 13. The head piece 14 may be threaded to the end of the tube 13 as indicated by the numeral 14` if desired.

Interposed between the head piece 14 and the flared portions of tube 12 and tubular member 9 is a series of rings 16 which are constructed of any desirable resilient material such as rubber for instance, or, if deemed desirable, coil springs or air bags may be used instead.

In order to hold the parts just described-in their proper relationship when the seaplane is in flight a cable 17 is provided for each of the resilient members. The cable 17 passes over the bushing 15 and is attached at both ends to an eye-bolt 18 by means of eyes formed in the cable which engage a short rod or stud which passes thru the opening in the eye-bolt as shown in Fig. 4. The eye-bolt 18 is adjustably supported by means of a member 19 which is mounted in a depression in the ski 1 directly beneath the pedestal 8. By means of a suitable adjusting screw 20 the slack in the cable may be taken up. The cable serves to prevent the weight of the ski from pulling the parts out of relationship while the seaplane is in Hight.

In order to provide greater strength and distribute the load more uniformly over the ski 1 metal plates 21 have been shown inserted between the bottom and second layers of wood directly below the pedestal 8. The bolts which fasten the pedestals 8 to the upper surface of the ski 1 pass thru and bear against these plates 21 and also pass thru holes in plates 22 upon which the pedestals rest. Plates 23 attached to the rear lower edge of the ski 1 serve to prevent splinteri-ng of the wood and prevent the excessive wear which would otherwise occur at this point.

A bolt 25 passing thru bushing 15 and a hole in a bracket 26 attached to the bottom of the pontoon 2 serves to attach the resilient members to the bottom of the pontoon.

The whole purpose of the construction just described is to absorb an shocks which may be caused by the skis striking the surface of 8, pivots 10 and the flared tubular members 9. The tube. 13 serves to hold the parts in alignment and as a guide over which the tube 12 and tubular member 9 may slide. It will be observed that the shape of the member 19 is such that a depression is formed iny the ski into which the tube 13 may enter at times when a severe shock causes the compression of the resilient material and consequently forces the lower end of the tube 13 down-` wardly toward the ski.

While a specific form of resilient member has been shown and described it is to be understood that it is not desired to limit the invention to the precise form shown in the drawings, but it is possible to use other forms equally as well and to vary the position and number of resilient members at will to suit conditions met inservice. l It might also be considered desirable at times to replace the resilient members just described with an airbag or rubber blocks interposed between the ski and thebottom of the pontoon throughout the length or part of the length of the ski.

The plurality of shock absorbers at the rear of the ski electually prevent sidesway of the ski owing to the length of the mounting pins and the slideby-side mounting of the absorber units. The channel members 3 also help to prevent side displacement of the ski and carry a lar e part of the load incident to sideslip in lan ing to the pontoon shell and frame.

It will be clearly seen from a study of the foregoing description and the attached drawings that this invention is admirably adapted tov perform the function of a landing gear for use on ice or snow and at the same .time does not interfere' with the use of the pontoons in water landing. This invention makes it possible to use a seaplane for long trips from a warm climate where little ice or snow may be encountered to much colder climate where the presence of ice and snow and absence of open water would make it impossible to land a plane without the risk of serious damage to the landing gear. Furthermore, the use of this invention'permits the removal of the skis whenever desired without disturbing the rest of the landing gear and be made without departing -from the spirit of the invention, and I do not therefore desire to limit myself to the specific construction shown and described but to interpret the invention broadly within the scope of the appended claims.

' What I claim as my invention is:

1. In a device of the class described, a water flotation body attached to and adapted to support the main body portion of the aircraft for landing on water, a plurality of members secured to the bottom of said body and forming a channel, and a ski positioned in said Channel and pivotally secured to said members at its forward end.

2. In a device of the cla-ss described, a water flotation body attached to and adapted to support the main body portion of the aircraft for landing on Water, a plurality of members secured to the bottom of said body and forming a channel, a ski positioned in said channel and pivotally secured to said members at its forward end and shock absorbing means 2o between the ski and the body.

3. In a device of the class described, a flotation body attached to and adapted to support the main body portion of the aircraft for landing on relatively fluid mediums, a

channel detachably secured to the bottom of said body, and a ski for landing on relatively solid vmediums detachably secured in said channel.

4. In a device of the class described, a Ilostation body for landing on relatively fluid mediums, a channel detachably secured to the bottom of said body, a ski for landing onrelatively solid mediums detachably secured in Said channel, and shock absorbing means between said ski and said body.

In testimony' whereof I unix my signature.

ARTHUR RALs'roN STALB, JR. 

